Sample Preparation Device for Quantitative Hydrogen Isotope Analysis Using Chromium Metal

A new technique for the sample preparation, directly coupled to an isotope ratio mass spectrometer (IRMS) for D/H determination, is described. The method is suitable for the preparation of fresh and saline waters as well as different organic compounds (gaseous or liquid). One microliter of water or hydrogen equivalent is injected and reduced by means of chromium metal in a specially designed reaction furnace, and then the hydrogen gas flows directly into the IRMS to be analyzed by standard/sample comparison. The reproducibility is about 1‰. The accuracy of this method is confirmed by analysis of IAEA standard waters VSMOW, GISP, and SLAP. All aqueous samples including liquid food samples as well as methane gas were injected as original compounds and directly measured without any preparation.